How do I send my email certificate (Digital ID) to someone else so that they can encrypt emails they send to me?

When you first receive your email certificate you will need to distribute the 'Public Key' to those people who you want to send encrypted emails to you. To do this send them an email and digitally sign it, this attaches the Public Key certificate to the email. They must store your email address with the certificate in their address book. After this they can then decide to encrypt each email that is sent to you by setting the 'Security Options'.